摘要
对比考察了多种溶剂介质中2-(5-溴-2-吡啶偶氮)-5-乙基氨基酚(5-B r-PADAP)吸收光谱,其吸收光谱形状与峰位随溶剂性质和浓度改变。以甲醇为溶剂时,浓度为1×10-5mol/L 5-B r-PADAP溶液的吸收峰出现显著红移。研究发现,吸收光谱随浓度有很大变化,染料主次吸收峰改变时的浓度与其共振散射峰出现时的浓度一致。试剂在不同溶剂中的核磁共振光谱亦有很大差异。探讨了染料光谱变化产生的原因及作用机理。
The UV-Vis absorption spectra of 2-[2-（5-bromo-pyridyl）azo]- 5-（diethylamino） phenol （5-Br-PADAP） in various solvents were studied. It was found that both the spectra shape and peak wavelength of 5-Br-PADAP are remarkably sensitive to the nature of the solvent in which it is measured and the concentration of the dye itself. In methanol, 1 × 10^-5 mol/L of 5-Br-PADAP exhibited a dramatic red-shift in comparison with that in ＂normal＂ solvents （ alcohols, water, etc. ）. The absorption spectra also changed with the concentration of 5-Br-PADAP, and the change trend is identical with that of resonance light scattering. The concentration where the main absorption peak changed to minor one was in accord with that where the peak of resonance light scattering appeared. The ^1H NMR spectra of 5-Br-PADAP in different solvents were also quite different. The mechanism of the spectra change of 5-Br-PADAP was discussed.
出处
《应用化学》
CAS
CSCD
北大核心
2006年第7期757-761,共5页
Chinese Journal of Applied Chemistry
基金
安徽省重点科研计划资助项目(0302206)
